This post originated from an RSS feed registered with .NET Buzz by Scott Hanselman. Original Post: A multi-request-safe ViewState Persister Feed Title: Scott Hanselman's ComputerZen.com Feed URL: http://radio-weblogs.com/0106747/rss.xml Feed Description: Scott Hanselman's ComputerZen.com is a .NET/WebServices/XML Weblog. I offer details of obscurities (internals of ASP.NET, WebServices, XML, etc) and best practices from real world scenarios. Latest .NET Buzz Posts Latest .NET Buzz Posts by Scott Hanselman Latest Posts From Scott Hanselman's ComputerZen.com

Mark Miller has posted his code for a ViewStatePersister using the "common sense but not obvious" GUID technique that was outlined previously by Scott Mitchell and myself.

He stores a GUID in the ViewState hidden field, and sticks the bloated ViewState in a temp file on the server.  It doesn't solve the problem when running multiple web servers while using stateless balancing (meaning: NOT using sticky sessions/node affinity) but it's the most elegant and complete solution I've seen yet and should work great on a single web server. 

A few questions I have though:

• When do the files get cleaned up and how often? Do you clean up old ones in a background thread within ASP.NET or a separate Windows Service?  Thought: I wonder if you could delete them after immediately after the Load?  You wouldn't be able to RE-post data, but it'd be cleaner, no?
• GUID generation is very expensive, and can really slow you down under load.  I wonder if it would be faster/easier to have a single long and use InterlockedIncrement or  InterlockedIncrement64 to safely increase the value on each call until it overflows and you start again at 0.

Many thanks to Mark for sharing!